If I run this block in an org file:

#+BEGIN_SRC emacs-lisp
(let ((org-export-before-parsing-hook '((lambda (_backend) nil))))
  (org-org-export-as-org))
#+END_SRC

I get a traceback that starts with

Debugger entered--Lisp error: (wrong-type-argument integer-or-marker-p nil)
  goto-char(nil)
  (if existing-result (goto-char existing-result) (goto-char (org-element-property :end inline)) (skip-chars-backward " \11"))

that seems to originate in 

  org-babel-insert-result(#<buffer *Org ORG Export*> ("value" "replace") ("emacs-lisp" "(let ((org-export-before-parsing-hook '((lambda (_..." ((:colname-names) (:rowname-names) (:result-params "value" "replace") (:result-type . value) (:results . "value replace") (:exports . "both") (:session . "none") (:cache . "no") (:noweb . "no") (:hlines . "no") (:tangle . "no") (:eval . "never-export")) "" nil 1 "(ref:%s)") nil "emacs-lisp")

If I put :results silent that doesn't happen. Is this a bug?

The org-file is empty in this case except for that block, but that doesn't seem to matter.